, the engine that connects us. >> and by the alfred p. sloan foundation. supportingscience,technology, andimproved economic performance and financial literacy in the 21st century. >> and with the ongoing support of these institutions and foundations. and... >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> suarez: rescuers worked in wet weather today to find survivors amid the rubble from the fiery explosion at a texas fertilizer plant last night. late today, authorities acknowledged there were fatalities but declined to confirm how many. earlier estimates ranged from five to 15 though there were reports the toll would go much higher. the cause of the fire and explosion is still not known; officials said today there's no evidence of foul play. a man using his cell phone captured the moment last night when the west fertilizer company plant exploded. that flattened buildings within a five blocks rand sent ockwes outiles around. >> i was actually picked up and th fy bout te end of m